NTSC
Video Measurements

Recognized with a technical Emmy award,
Tektronix' world-class core competencies have enabled it to design
and deliver the most comprehensive video measurement solutions in
the industry.

Recognized as the de facto industry standard
that keeps pace with evolving customer needs, the VM700T is a total
solution for your baseband video and audio monitoring and measurement
needs. Features such as an extremely fast and fully automatic measurement
mode as well as full manual operation provides the first-time user,
as well as the seasoned professional, an unequaled value for their
test and measurement investment.

Automatic Video Measurement
Set

The VM700T Auto mode makes standard video transmitter
measurements quickly and automatically, including those specified
in RS-250C/EIA-250C, NTC-7, and RS170A. Both vertical interval and
full field measurements can be made and compared with user-defined
limits. A dual limit verification system is employed to generate a
caution or alarm message when either limit is violated. Reports can
be generated and printed automatically at operator-scheduled times
or triggered from a conditional event.

Graphic Displays of
Measurements

Main measure mode display
of available measurements.

Measure mode
DGDP special position acquisition feature.

Measure mode provides virtual real-time graphic displays of measurement
results automatically. Vertical interval or full field measurements
including noise spectrum, group delay, K-Factor, differential gain,
and differential phase are presented as clever, easy-to-understand
interactive digital displays. Such displays are indispensable when
extremely fast measurement update rates (up to 30 times a second)
are required to provide instant feedback of critical adjustments and
analysis of signal variations. User-definable limits are visually
integrated into each graphic display and can be used to trigger a
measurement report or a user-definable macro function. Such a function
can, for example, dial out through a modem to report measurement results
or control a signal router. A relative to reference mode allows normalizing
to a signal source or eliminate signal path errors from the desired
measurement. Up to 2 video references can be stored in NVRAM. Additionally,
after downloading to a PC through the VM700T FTP driver, the video
reference can be uploaded to another VM700T for reuse. A running averaging
mode can be used to reduce the effect of noise. When additional measurement
data is required, a user can custom configure measurement parameters
and report format.

Digital
Waveform Monitor/Vectorscope

The VM700T Waveform mode application
provides real-time graphics displays of the video signal allowing
many additional measurements to be made manually. Easy-to-use measurement
cursors are available to measure time, frequency, and amplitude parameters
of a video signal. These cursors allow a very quick and precise location
of the 10%, 50%, and 90% points on any transition. Cursor mode also
employs an automatic calculation in the wave shape in the center of
the display. The parameters calculated are sine peak-to-peak amplitude,
frequency, and offset from blanking level. This is very useful for
frequency response measurements with the Multiburst signal.

The waveform display can be expanded around any point both vertically
and horizontally. Since the data is digitized, the display remains
bright and easy to read at all expansion factors. The scales automatically
expand with the waveform, so all units are correct as displayed. A
channel difference mode (A-B, A-C, B-A, B-C, C-A, and C-B) is also
provided. A screen memory selection enables Envelope mode, which is
useful for looking at teletext, Jitter, or other changes over time.

In Vector mode, the VM700T becomes a digital vectorscope
with an electronic graticule. A "Color Bar Search" feature makes it
easy to quickly display a line containing a color bar test signal.

Vector mode provides the normal vectorscope display.
The vectors may be rotated or expanded, with the rotation angle and
gain values displayed numerically on the screen.

Vertical interval test signals can be seen very clearly
for additional analysis of the signal. These can be printed as support
documentation for automatic measurement results.

A unique "Find Color Bars" feature searches all video for Color
Bars and displays the vectors if found. The vectors can be referenced
to either the selected channel's burst or the burst of one of the
other two channels or continuous subcarrier. The phase difference
between the selected channel and the reference is always displayed.

Select Line in both Waveform and Vector modes can be used to
quickly specify any line for display or automatic measurement if it
is the proper signal.

Picture Mode

Picture Mode
display. (Video courtesy of KOIN-TV, Portland, Oregon)

Even a single horizontal synchronization pulse
can be displayed at a high intensity.

The signal
source can be quickly verified using the picture display. Additionally,
a "bright-up" line select mode allows a user to select any video line
for use in Measure mode or for viewing in Waveform or Vector mode.

User-programmable Functions

Function mode is an extremely
powerful feature that allows a user to store a sequence of user operations
as a macro function for later "playback."

For example, a set
of measurements (complete with hardcopy commands) to be made on a
transmitter demodulator video output, could be stored as a function
labeled "DEMOD." The function "playback" could then be initiated manually,
remotely, or completely automatically as a user-specified timed event.
Function files can be stored as a text file on a PC for editing, copying,
or uploading to another VM700T. Other function capabilities include
controlling of external serial devices such as video/audio routers,
switchers, signal generators, telephone modems, and many other devices
which support RS-232 communications.

Hardcopy

All
information on the screen may be printed in high-resolution graphics
on printers supporting PostScript, Hewlett-Packard LaserJet, DeskJet
and ThinkJet, or 24-Pin Epson graphics through the Centronics-compatible
parallel port or standard RS-232C interface.

Automatic measurement
results in text format can be printed on most ASCII printers using
the parallel or serial ports.

Remote Operation

The
VM700T has a powerful and fully documented remote control language.
The VM700T can thus be operated from a remote terminal using RS-232C
to monitor unattended transmission systems. In addition, all files
can be uploaded to a main computer and downloaded to other VM700Ts.
Two different protocols are supported: FTP (File Transfer Protocol)
and TELNET. The user can also select a "no protocol" mode of the RS-232C
interface when dealing with low baud rates. However, file transfers
can only take place with FTP.

Characteristics

The performance requirements
cited in this section are valid only within the following environmental
limits:

Temperature range of 0 to 50 °C, with a minimum
warm-up time of 20 minutes. The following tables list each measurement
and its performance requirement

The range specifies the extremes
between which a measurement can be made

All measurement accuracies
specified are valid only with nominal input signals of 1 Vp-p (±6 dB) with an unweighted signal-to-noise ratio of at least 60 dB
on the incoming signal and a termination accuracy of ±0.025% (Tektronix
PN 011-0102-xx or equivalent)

Measure Mode*1,
2

*1 All accuracies for measurements with
averaging capabilities assume the default average of 32.

*2 All accuracies for measurements with relative to reference
mode assume an average of 256 was used to create the reference.

Bar line time measurement.

Bar Line Time

Measurement

Range

Absolute Mode Accuracy

Relative Mode Accuracy

Bar Level

50 to 200 IRE

±0.5%

±0.2%

Sync Level

20 to 80 IRE

±0.5%

±0.2%

Sync to Bar Top

70 to 280 IRE

±0.5%

±0.2%

Sync/Bar Ratio

10% to 125% 100% nominal

±0.5%

±0.2%

Bar Tilt (Rec 569)

0 to 20%

±0.2%

±0.1%

Line Time Distortion (Rec 567)

0 to 20%

±0.2%

±0.1%

Bar Width

10 μs to 30 μs

±100 ns

NA

Bounce

Measurement

Range

Accuracy

Peak Deviation

0 to 50%

±1%

Settling Time

0 to 10 s

±100 ms

Burst Frequency*3

Measurement

Range

Relative Mode Accuracy

Burst Frequency Error

±100 Hz

±0.5

*3 Requires a reference signal.

Chrominance-to-Luminance gain and delay measurement.

Chrominance-to-Luminance Gain and Delay

Measurement

Range

Absolute Mode Accuracy

Relative Mode Accuracy

Chrominance-to- Luminance Delay

±300 ns

±5 ns

±1.0 ns

Chrominance-to- Luminance Gain Ratio

0 to 160%

±1.0%

±0.1%

Chrominance Frequency Response

Measurement

Range

Absolute Mode Accuracy

Relative Mode Accuracy

Reference Amplitude

0 to 100 IRE

±1%

±0.5%

Frequency Response

0 to 100 IRE

±1%

±0.5%

Chrominance Noise

Measurement

Range

Absolute Mode Accuracy

AM Noise

-20 to -80 dB

±1 dB (-20 to -60 dB)

PM Noise

-20 to -70 dB

±1 dB (-20 to -60 dB)

Chrominance nonlinearity measurement.

Chrominance Nonlinearity*4

Measurement

Range

Absolute Mode Accuracy

Relative Mode Accuracy

Chrominance Amplitude

0 to 100%

±0.4%

±0.2%

Chrominance Phase

0 to 360°

±1°

±0.2°

Chrominance-to- Luminance Intermodulation

-50 to +50%

±0.2%

±0.2%

*4 Accuracies for chrominance nonlinearity
amplitude and phase measurements assume an average of 256.

Color bar measurement.

Color
Bar

Measurement

Range

Absolute Mode Accuracy

Relative Mode Accuracy

Luminance Level

0 to 100 IRE

(0 to 714.3 mV)

±0.5 IRE

±0.2%

Chrominance Level (excluding gray and black)

0 to 100 IRE

(0 to 714.3 mV)

±1.0% of nominal

±0.2%

Chrominance Phase

±180° of nominal

±0.5° of nominal

±0.1°

SMPTE Color Bars Nominal Values

Color

LUM (mV)

Chroma P-P (mV)

Phase (Degrees)

Yellow

494.6

444.2

167.1

Cyan

400.4

630.1

283.4

Green

345.9

588.5

240.8

Magenta

256.7

588.5

60.8

Red

202.2

630.1

103.4

Blue

108.1

444.2

347.1

Differential gain and phase measurement.

Differential Gain and Phase

Measurement

Range

Absolute Mode Accuracy

Relative Mode Accuracy

Differential Gain

0 to 100%

±0.3%

±0.03%

Differential Phase

0 to 360°

±0.3°

±0.03°

Frequency response and group delay measurement
using Sin x/x.

Frequency Response and Group
Delay

Measurement

Range

Absolute Mode Accuracy

Relative Mode Accuracy

Frequency Response

±40 dB

±1.0 dB

±0.3 dB

Group Delay

±1.0 μs

±20 ns

±5 ns

Horizontal Blanking

Measurement

Range

Absolute Mode Accuracy

Blanking Start

0.1 to 4.2 μs

±50 ns

Blanking End

6.8 to 12.2 μs

±50 ns

Blanking Width

6.9 to 16.4 μs

±50 ns

Horizontal timing measurement.

Horizontal Timing

Measurement

Range

Absolute Mode Accuracy

Burst Level

10 to 80 IRE

±0.5%

Horizontal Sync Rise and Fall Time

80 ns to 1 μs

±10 ns

Horizontal Sync Width

3 to 7 μs

±10 ns

Burst Width

6 to 13 cycles

±0.1 cycles (FCC) ±0.5 cycles (RS-170A)

Sync to Burst Start (RS-170A)

4 to 10 μs

±150 ns

Sync to Burst End (FCC)

4 to 10 μs

±25 ns

Front Porch

0.1 to 3.5 μs

±10 ns (FCC) ±10 ns (RS-170A)

Sync to Setup

8.8 to 13.0 μs

±10 ns

Breezeway (FCC)

0.1 to 5 μs

±25 ns

Sync Level

20 to 80 IRE

±0.5%

Incidental Carrier Phase Modulation

Measurement

Range

Accuracy

ICPM (requires Zero Carrier Pulse and the quadrature output
of the demodulator on Channel C)

0 to 90°

±1.0°

H Jitter.

Jitter

Measurement

Range

Absolute Mode Accuracy

Jitter (2 field)

±20 μs

±10 ns

Jitter Long Time

±20 μs

±10 ns

K-Factor measurement.

K-Factor

Measurement

Range

Absolute Mode Accuracy

2T Pulse K-Factor

0 to 10% Kf

±0.3%

KPB

10 to 5% KPB

±0.3%

Pulse-to-Bar Ratio

10 to 125%

±0.7%

Pulse Half Amplitude Duration (HAD)

100 to 500 ns

±5 ns

Level meter measurement.

Level Meter

Measurement

Range

Accuracy

Level Meter

0 to 1.4 V

±3.5 mV

Line Frequency

Measurement

Range

Accuracy

Line Frequency

±3%

±0.1%

Field Frequency

±3%

±0.1%

Luminance nonlinearity measurement.

Luminance Nonlinearity

Measurement

Range

Absolute Mode Accuracy

Relative Mode Accuracy

Luminance Nonlinearity

0 to 100%

±0.4%

±0.2%

Multiburst measurement.

Multiburst*5

Measurement

Range

Absolute Mode Accuracy

Relative Mode Accuracy

Reference Flag or Packet Amplitude

30 to 130 IRE

±1%

NA

Other Packets

-40 to +6 dB

±0.1 dB

±0.03 dB

*5 Total Harmonic Distortion on packets
must be ≤46 dB.

Noise spectrum measurement.

Noise Spectrum

Measurement

Range

Absolute Mode Accuracy

Unweighted Signal-to-Noise Ratio (5 MHz Low Pass)

-20 to -80 dB

±0.4 dB (-20 to -60 dB)

±1.0 dB (-60 to -70 dB)

Weighted Signal-to-Noise Ratio (5 MHz Low Pass and Unified
Weighting)

-20 to -80 dB

±1.0 dB (-20 to -0 dB)

±2.0 dB (-60 to -70 dB)

SCH phase measurement.

SCH Phase

Measurement

Range

Absolute Mode Accuracy

SCH Phase

±90°

±5°

Sync Timing

±1 μs

±10 ns

Burst Timing

±180°

±5°

Vertical blanking display.

Vertical blanking serration pulse measurement.

Vertical Blanking

Measurement

Range

Absolute Mode Accuracy

Equalizing Pulse Width

80 ns to 1 μs

±10 ns

Serration Pulse Width

80 ns to 1 μs

±10 ns

Auto Mode

RS-170A Horizontal Blanking
Interval Timing Measurements

Measurement

Range

Accuracy

Test Signal

Color Burst Width

6 to 13 cycles

±0.1 cycles

Horizontal Blanking

Front Porch Duration

0.5 to 2 μs

±20 ns

Horizontal Blanking

Horizontal Blanking Width

6 to 30 μs

±50 ns

Horizontal Blanking

Horizontal Sync Rise Time and Fall Time

80 to 120 ns, 120 to 300 ns, 300 ns to 1.0 μs

-10 to +30 ns, ±20 ns, ±30 ns

Horizontal Blanking

Horizontal Sync Width

1 to 8 μs

±10 ns

Horizontal Blanking

SCH Phase

±90°

±5°

Horizontal Blanking

Sync to Setup

5 to 18 μs

±20 ns

Horizontal Blanking

Sync to Start of Burst

4 to 8 μs

±140 ns (0.5 cycles),

±20 ns

Horizontal Blanking

RS-170A Vertical Blanking Interval

Measurement

Range

Accuracy

Test Signal

Equalizing Pulse Width

1 to 20 μs

±10 ns

Vertical Blanking

Serration Width

1 to 20 μs

±10 ns

Vertical Blanking

Vertical Blanking Width

19 to 29 lines

-0.1 lines to +0.2 lines

Vertical Blanking

FCC Horizontal Blanking Interval Timing Measurements

Measurement

Range

Accuracy

Test Signal

Breezeway Width

0.2 to 3.5 μs

±25 ns

Horizontal Blanking

Color Burst Width

6 to 13 cycles

±0.1 cycles

Horizontal Blanking

Front Porch Duration

0.5 to 2 μs

±10 ns

Horizontal Blanking

Horizontal Blanking Width

6 to 30 μs

±10 ns

Horizontal Blanking

Horizontal Sync Rise Time and Fall Time

80 to 120 ns, 120 to 300 ns, 300 ns to 1.0 μs

-10 to +30 ns, ±20 ns, ±30 ns

Horizontal Blanking

Horizontal Sync Width

1 to 8 μs

±10 ns

Horizontal Blanking

Sync to Setup

5 to 18 μs

±20 ns

Horizontal Blanking

Sync to End of Burst

6 to 15 μs

±20 ns

Horizontal Blanking

FCC Vertical Blanking Interval Timing Measurements

Measurement

Range

Accuracy

Test Signal

Equalizing Pulse Width

25 to 100%, of nominal horizontal sync pulse width

±0.3%

Vertical Blanking

Serration Width

1 to 20 μs

±10 ns

Vertical Blanking

Vertical Blanking Width

19 to 29 lines

-0.1 lines to +0.2 lines

Vertical Blanking

Amplitude and Phase Measurements

Measurement

Range

Accuracy

Test Signal

Average Picture Level (APL)

0 to 200%

±3.0%

Full Field

Bar Top

0 to 90% of Maximum Carrier

±0.1%

FCC/NTC-7 Composite

Bar Amplitude

0 to 200 IRE

±0.3 IRE

FCC/NTC-7 Composite

Chrominance-to- Luminance Delay (Relative Chroma Time)

±300 ns

±5 ns

FCC/NTC-7 Composite

Chrominance-to- Luminance Gain (Relative Chroma Level)

0 to 160%

±1%

FCC/NTC-7 Composite

Differential Gain

0 to 100%

±0.3%

FCC/NTC-7 Composite

Differential Phase

0 to 360°

±0.3°

FCC/NTC-7 Composite

Luminance Nonlinear Distortion

0 to 50%

±0.4%

FCC/NTC-7 Composite

Relative Burst Gain

±100%

±0.3%

FCC/NTC-7 Composite

Relative Burst Phase

±180°

±0.3°

FCC/NTC-7 Composite

Burst Amplitude

(% of sync)

25 to 200% of sync

±1.0%

Horizontal Blanking

Burst Amplitude

(% of bar)

10 to 80% of bar (10 to 80 IRE when bar is not used)

±0.4% (±0.4 IRE)

Horizontal Blanking

Sync Amplitude

(% of bar)

20 to 80% of bar (20 to 80 IRE when bar is not used)

±0.3% (±0.3 IRE)

Horizontal Blanking

Blanking Level

0 to 90% of Maximum Carrier

±0.2%

Horizontal Blanking

Sync Variation

0 to 50% of Maximum Carrier (0 to 50% of bar when Zero Carrier
is not used and 0 to 50 IRE when Zero Carrier and bar are not used)

±0.3% for Zero Carrier (±0.3% for bar and ±0.3 IRE for no
Zero Carrier and no bar)

Horizontal Blanking

Blanking Variation

0 to 50% of Maximum Carrier (0 to 50% of bar when Zero Carrier
is not used and 0 to 50 IRE when Zero Carrier and bar are not used)

±0.3% for Zero Carrier (±0.3% for bar and ±0.3 IRE for no
Zero Carrier and no bar)

Horizontal Blanking

Frequency Response Measurements

Measurement

Range

Accuracy

Test Signal

Multiburst Flag Amplitude

0 to 90% of Maximum Carrier (20 to 130% of bar when Zero Carrier
is not used and 20 to 130 IRE when Zero Carrier and bar are not used)

±0.5% for Zero Carrier (±0.5% for bar and ±0.5 IRE for no
Zero Carrier and no bar)

FCC Multiburst or NTC-7 Combination

Multiburst Packet

0 to 100% of Flag NTC-7 Combination

±1% of Flag

FCC Multiburst or Amplitudes

Incidental Carrier Phase Modulation

Measurement

Range

Accuracy

Test Signal

ICPM (requires Zero Carrier Pulse and the quadrature output
of the demodulator on Channel C)

0 to 30°

±1.0°

FCC or NTC-7 Composite

Color Bar Measurements

Measurement

Range

Accuracy

Test Signal

Color Bar Amplitude Errors

±100% of nominal

±1.0%

FCC Color Bars

Color Bar Phase Errors

±180° from nominal

±0.5°

FCC Color Bars

Color Bar Chrominance-to- Luminance Gain Ratio

0 to 200% of nominal

±2%

FCC Color Bars

Out-of-Service Measurements

Measurement

Range

Accuracy

Test Signal

Field Time Distortion

0 to 40%

±0.5%

Field Square Wave

Waveform Distortion Measurements

Measurement

Range

Accuracy

Test Signal

Line Time Distortion

0 to 40% of bar

±0.2%

FCC or NTC-7 Composite

Pulse-to-Bar Ratio

10 to 125%

±0.7%

FCC or NTC-7 Composite

Short Time Waveform Distortion

(IEEE 511)

0 to 25% SD

±0.5% SD

NTC-7 Composite

Chrominance Nonlinear Gain Distortion

5 to 35 IREE

(20 IRE chroma)

45 to 160 IRE

(80 IRE chroma)

±0.4 IRE

NTC-7 Combination

Chrominance Nonlinear Phase Distortion

0 to 360°

±1.0°

NTC-7 Combination

Chrominance-to- Luminance Intermodulation

±50 IRE

±0.2 IRE

NTC-7 Combination

2T K-Factor

0 to 10% Kf

±0.3% Kf

FCC or NTC-7 Composite

VIRS Measurement

Measurement

Range

Accuracy

Test Signal

VIRS Setup (Reference Black)

-20 to 130% of bar (-20 to J321 130 IRE when bar is not used)

±0.2% (±0.5 IRE when bar is not used)

VIRS

VIRS Chrominance Reference Amplitude

0 to 200% of burst amplitude (0 to 80% of bar when burst is
not used and 0 to 80 IRE when burst and bar are not used)

±1% (±0.1% when burst is not used and ±1 IRE when burst and
bar are not used)

The
following paragraphs describe the measurement methods for each measurement.
Each timing measurement method is written for the FCC method. If there
is an RS-170A method for that same measurement, and the RS-170A method
differs from the FCC method, the RS-170A requirement is enclosed within
square brackets in the FCC description.

Horizontal Interval
Timing Measurements

These timing measurements are made
within the active picture area, averaging the results over 32 lines
starting at line 50 and skipping 1 frame plus 5 lines for each successive
sample (i.e., average over line 50 of first field, line 56 of second
field, line 62 of the third field, etc.).

Breezeway
Width: Measured from the 10% point on the trailing edge of horizontal
sync (nominally -4 IRE) to the leading half-amplitude point of the
burst envelope.

Color Burst Width: Measured from
the leading half-amplitude point on the burst envelope [leading zero
crossing of the first half-cycle of burst that exceeds 50% of burst
amplitude] to the trailing half-amplitude point on the burst envelope
[trailing zero crossing of the last half-cycle of burst that exceeds
50% of burst amplitude].

Front Porch Duration: Measured
from the 10% point on the trailing edge of setup (+4 IRE nominally)
to the 10% [50%] point on the leading edge of sync (nominally -4 [20]
IRE).

Horizontal Blanking Width: Measured between
the points on the leading and trailing edges of horizontal blanking
that are at an amplitude of 10% [50%] of sync above blanking level
(nominally +4 [+20] IRE).

Horizontal Sync Rise Time and
Fall Time: Measured between the 10% and 90% points on the leading
and trailing edges of horizontal sync, respectively (nominally -4
IRE and -36 IRE).

Horizontal Sync Width: Measured
between the 10% [50%] points on the leading and trailing edges of
horizontal sync (nominally -4 [-20] IRE).

SCH Phase: Phase at the middle of burst relative to the 50% point on the sync
leading edge.

Sync to Setup: Measured from the 10%
[50%] point on the leading edge of sync (nominally -4 [-20] IRE) to
the point on the trailing edge of blanking that is equivalent to 10%
of sync (nominally +4 IRE).

Sync-to-Start of Burst: Measured from the 50% point on the leading edge of sync (nominally
-20 IRE) to the leading zero crossing of the first half-cycle of burst
that exceeds 50% of burst amplitude.

Sync-to-End of Burst: Measured from the 10% point on the leading edge of horizontal sync
(nominally -4 IRE) to the half-amplitude point on the trailing edge
of the burst envelope.

Color Bar Amplitude Error: Measured as deviation of the
peak-to-peak amplitude of each color bar from the nominal value for
that color bar expressed as a percent of the nominal value. Six values
reported.

Color Bar Phase Error: Measured as deviation
of the phase of each color bar from the nominal phase for that color
bar, relative to burst phase. Six values reported.

Color
Bar Chrominance-Luminance Gain Ratio: Measured as ratio of chrominance
level to luminance level of each color bar, relative to the nominal
ratio for each color bar. Six values reported.

Color Bar
Values

Color

Amplitude

Phase

C/L Gain Ratio

Yellow

67.36%

167.59°

1.0092

Cyan

94.74%

283.54°

1.8045

Green

89.04%

240.67°

2.0123

Magenta

89.04%

60.67°

2.8957

Red

94.74%

103.54°

4.2106

Blue

67.36%

347.59°

8.1652

Amplitude and Phase Measurements (FCC or NTC-7
Composite VITS)

VITS ID display.

Bar Top: Measured as the ratio of the
bar top to Zero Carrier amplitude to the blanking (at back porch)
to the Zero Carrier amplitude. Result expressed as a percent of Max
Carrier.

Bar Amplitude: Measured from the reference
blanking level (at back porch) contained within the test line to the
level at the center of the bar.

Burst Amplitude:
VITS not required. Burst amplitude must be at least 10 IRE. Measured
as peak-to-peak amplitude of the color burst at burst center.

Chrominance-Luminance Delay Inequality (Relative Chrominance
Time): Measured as the time difference between the luminance component
and chrominance component of the modulated 12.5T pulse.

Chrominance-Luminance Gain Inequality (Relative Chrominance Level): Measured as the peak-to-peak amplitude of the chrominance component
of the modulated 12.5T pulse.

Differential Gain:
Measured as the absolute amplitude difference between the smallest
and largest staircase chrominance packets. Result expressed as a percent
of the largest packet amplitude.

Differential Phase: Measured as the largest difference in phase between any two staircase
chrominance packets.

Luminance Nonlinear Distortion: Measured as the difference between the largest and smallest step
amplitudes of the staircase at the center of each step. Result expressed
as a percent of the largest step amplitude difference.

Relative Burst Gain: Measured as the difference between the peak-to-peak
amplitude of burst and the staircase chrominance packet located at
blanking. Result expressed as a percent of the packet amplitude.

Relative Burst Phase: Measured as the difference in
phase between the color burst and the staircase packet located at
blanking.

Sync Amplitude: Measured from the tip of
the horizontal sync pulse to blanking level.

Blanking
Level: Measured as the ratio of the blanking (at back porch) to
Zero Carrier amplitude to the sync tip to Zero Carrier amplitude.
Result expressed as a percent of Max Carrier.

Sync Variation: Measured as the peak-to-peak variation of the horizontal sync pulse
amplitude within every third line of a field.

Blanking
Variation: Measured as the peak-to-peak variation of the blanking
level within every third line of a field.

Multiburst Flag Amplitude: Measured from back
porch blanking to the center point of the flag top.

Multiburst
Amplitude: Measured as the peak-to-peak amplitude of each of the
multiburst packets. Six results reported.

Waveform
Distortion Measurements (FCC or NTC-7 Composite VITS)

Line Time Distortion: Measured as the peak-to-peak amplitude
change of the bar top, excluding the first microsecond and the last
microsecond.

Pulse-to-Bar Ratio: Measured as the
peak amplitude of the 2T pulse, expressed as a percent of the bar
amplitude.

Short Time Waveform Distortion: Measured
as a weighted function of time, the result is the peak deviation from
flatness within 1 ms of the center of a bar transition. ANSI/IEEE
Std.-511-1979, Section 4.4, Appendix B.

Chrominance Nonlinear
Gain Distortion: Measured as the peak-to-peak amplitude of the
first (nominally 20 IRE) and last (nominally 80 IRE) chrominance packets
in the 3-level chrominance signal, referenced to the peak-to-peak
amplitude of the middle packet (nominally 40 IRE).

Chrominance
Nonlinear Phase Distortion: Measured as the difference between
the largest and the smallest deviation in phase among the 3-level
chrominance test signal subcarrier packets.

Chrominance-to-Luminance
Intermodulation: Measured using the 3-level chrominance test signal.
Result is the maximum amplitude departure of a filtered part of the
luminance pedestal from a part of the pedestal upon which no subcarrier
has been superimposed.

2T Pulse K-Factor: Measured
as the greatest weighted amplitude of a positive-going or negative-going
echo-term half-wave which is within 1 μs before the 2T pulse leading
edge half-amplitude point or within 1 μs after the 2T pulse trailing
edge half-amplitude point. Result expressed as a K-Factor which is
the ratio of the weighted amplitude of the echo-term half-wave to
the sampled amplitude of the 2T pulse.

VIRS Setup
(Reference Black)

VIRS Chrominance Reference
Amplitude: Measured from the blanking level included in the test
signal to setup level.

VIRS Chrominance Phase Relative
to Burst: Measured as the amplitude of the VIRS chrominance packet,
expressed as a percent of burst (or percent of bar if no burst).

Measured from the blanking level included in the test signal to luminance
reference level (nominally 50 IRE).

Unweighted SNR: Measured as the ratio of bar amplitude to the unweighted RMS amplitude
of the noise on a quiet line.

Luminance Weighted SNR: Measured as the ratio of bar amplitude to the luminance-weighted
RMS amplitude of the noise on a quiet line.

Periodic
SNR: Measured as the ratio of bar amplitude to the peak-to-peak
value of the periodic noise.

Out-of-Service Measurements

Long Time Distortion: Measured as the peak
overshoot and settling time in a flat field test signal switched from
10% to 90% APL in less than 10 μs.

Field Time Distortion: Measured as the peak-to-peak amplitude change of the 100 IRE field
squarewave top. The first and last 250 μs are excluded. Expressed
as a percent of the field squarewave amplitude.